Parents of prodigies have long struggled with that fine line, and Jong’s involvement with Kim’s career is unmatched in snowboarding. He saw genius in his daughter.

“When she was 8,” Jong said, “I thought, ‘Well, maybe I can bring her to the Olympics.’ ”

So he quit his job and devoted his life to Kim. She moved to Geneva to live with her aunt. When Jong visited, they went to France so she could ride the halfpipe in Avoriaz. He accompanied her around the world at 10, when she would show up to competitions and flummox organizers that couldn’t fathom a girl this young, this good. Whatever potholes presented themselves – “Girls are kind of very difficult to take care of,” Jong said – were filled in with the promise of what was to come.

Now, Kim, once she turns 18 on April 23, is set to become one of the most marketed athletes in the United States. She already has sponsorship deals with Nike, Burton, Toyota, Visa, Samsung, Target, Mondelez, and Monster, among others. After winning the gold, she gained more than 66,000 Twitter followers in a span of about 30 minutes.

She had fewer than 10,000 followers when the Games began. A week ago, her follower account was approaching 208,000. At the time of this writing, her total is up to 328,000.

“The cool part about somebody like Chloe Kim is that she’s an absolutely delightful 17-year-old who’s funny to follow anyway, and then all of a sudden she goes out and just crushes it,” Lavielle said. “So she’s a hero because she’s crushing it for the U.S., but on the other hand, she’s completely approachable and normal, because she’s tweeting about how she’s hangry.”

ChloeKim, of the United States, celebrates winning gold in the women’s halfpipe finals at Phoenix Snow Park at the 2018 Winter Olympics in Pyeongchang, South Korea, Tuesday, Feb. 13, 2018. (AP Photo/Gregory Bull)